Grinding disk



Sept. 19, 1939. H. HIPPLE 3 5 Grimme DISK Filed Sept. so; 1937 Patent ed Sept. 19, 1939 I I UNITED STATES PATENT OFFICE GRINDING DISK Hermann Hipple, Munich, Germany, assignor, by mesne assignments, to Franz Forg, Solln, near Munich, Germany Application September 30, 1937, Serial No. 166,502 In Germany October 5, 1936 9 Claims. ((31. 51-206) My invention relates to grinding disks and has ing disk and the mode of mounting the same for its general object to devise an improved Within a carrier preventing against bursting of grinding disk for grinding surfaces, grooves, the disk during rotation, and Fig. 2 a similar threads or the like on cylindrical work-pieces. section showing in particular the mode of mount- 5 Further objects of my invention consist therein ing and assembling the grinding disk within said 5 to provide a grinding disk of specific conformacarrier, tion and arrangement with a view of improving Referring more particularly to the drawing; the process of grinding and of avoiding the centhe grinding disk consists of an annular body I, trifugal forces arising during rotation of the the interior circular edge thereof being adapted o grinding disk against injuriously acting into the to act as grinding surface, 'while the exterior latter. circular edge or periphery of said annular body is Heretofore grinding disks have been confully'surrounded by the margin 4 of a pot-shaped structed and operated in such a manner that the carrierZ at a distance from the bottom or' plategrinding is performed along the exterior periphshaped portion of the latter. The annular grindcry of the disk. The known constructions of ing body or disk ,I, more particularly, is sup- 15 grinding disks areconnected with certain disadported in said pot-shaped carrier 2 within a cirvantages firstly in that the process of grinding cular depression provided alongside theinterior could not be carried out in a fully satisfactory of the circular rim of said carrier, a ring of yieldmanner and secondly in that no provisions could ing material 3 being interposed between the rear be made to avoid bursting of the disk due to cenmarginal surface of said annular grinding body 20 trifugal forces arising during rotation thereof. or disk I and an annular projection I! limiting In known constructions of grinding disks the relsaid circular depression in inward direction of atively unfavorable conditions of grinding could said carrier 2. Said grinding disk I is further only be improved to some extent by using grindfirmly seated within said circular depression by mg disks of large diameter in order to ensure means of an annular metal body or fillet 6 cast 5 as much as possible a grinding along an approxiinto the annular space between the tapering pormately straight line. Grinding disks of large tion of the outer surface-of said disk I and the diameter, however, are particularly exposed to annular grooves 5 formed along'the front porthe danger of bursting, as no provisions can be tion of the interior surface of said circular demade on such disks to protect them against the pression provided along the interior of the mar- 30 action of centrifugal forces. gin 4 of said pot-shaped carrier 2. In case of.

By my invention the aforementioned disadvangrinding machines for making the threads of tages inherent to grinding disks of the ordinary screw-bolts, the work-piece I is moved in-known construction will be fully avoided and, in addimanner with respect to the interior wedge-shaped tion, thegeneral conditions of grinding may be grinding surface of the disk I, while at some 35 essentially improved. other place of said grinding surface there is pro- According to my inventionthe grinding disk is vided a diamond 8 guided by a proper device constructed in the form of an annular body preforming part of the machine in a manner to slide senting a grinding surface along its interior along the profile of the grinding surface to periphery which for this purpose is of a cross- 'sharpen the latter. The pot-shaped carrier 2 40 sectional conformation in agreement with the surrounding at its margin 4 the grinding disk I is shape to be given to the work-piece bythe operapressed onto the conical portion ID of the mation of gr d AS result of this COIIStIUC- chine shaft H by means of a nut Q threaded onto tion, in the fi t place, h center-points 0f the the end of said'shaft II. The pot-shaped carrier curvatures of the grinding surface and of the 2 now will serve to effectively suppress the action 45 p ph y of the Wo -p c to b Subjected to of centrifugal forces arising within the grinding grinding are positioned both on one and the same disk I thus protecting the latter against bursting side of the grinding surface, and in the second even. at high peripheral speeds. Said carrier 2, place the grinding disk may be effectively pro- -m0reover, consists of a material of great metected against the action of centrifugal forces. chanical strength able to withstand the centrii- 50 In the accompanying, drawing which forms ugal forces arising at the highest peripheral part of this specification I have represented an speeds. In the bottom or plate-shaped part of example of a construction of my new grinding the carrier 2 there are provided uniformly disdisk, Fig. 1 being a section partly in view, showtributed apertures [2 serving for discharging the iiig the general conformation of my novel grindcooling or lubricating medium.

30 the grinding disk l, thereby pressing the latter Mynew grinding disk is inserted into the carrier 2 according to my invention in the following manner. The carrier 2 is placed according to Fig. 2 with its axis in vertical direction onto the conical portion l3 of the machine shaft and thereupon the annular grinding disk I is pressed onto the yielding ring 3 resting on the annular projection I! (Fig. 1) which limits the circular depression within the interior of the margin 4 of the carrier 2. The disk I, moreover, is pressed into the carrier 2 in cold condition of the latter in a manner to secure a firm seat of the disk in the carrier'and to avoid' any eccentricity of the center of gravity of the disk. After inserting the disk I into the carrier 2 the tapered portion of the former will be positioned radially opposite the grooves 5. Upon heating the carrier 2, for instance by means of a heating bandage l8, owing to the expansion of the carrier there will be formed a narrow annular gap between the margin 4 of the carried and the disk I, said gap being covered up by means of a cord l9 serving to prevent cast metal 6 against flowing into said gap.

Subsequent to removing the heating bandage i8 the whole of the disk and carrier will become cool and the cast metal d solid, whereupon the pressure plate i4 is taken off by unscrewing the threaded nut l5. Now the yielding ring 3 which had previously been kept in compressed condition will come into action and exert a pressure onto at its tapered portion with a uniform force outwardly against the cast-in metal 6, which will thus be kept safely within the depression by means of the grooves 5. In this manner any displacement of the disk I within its carrier 2 will be safely prevented.

Fastening of the grinding disk I in the carrier 2 may also be accomplished in that the annular gap formed between the margin 4 of the carrier 2 and the disk I is not covered up against cast metal flowing thereinto, so that the latter may protrude as far as to the yielding ring 3.

I claim:

1. A grinding disk of annular conformation, the interior periphery of said disk being adapted to act as a grinding surface, said disk being seated under pressure along its exterior periphery within a carrier in a circular depression provided along the interior periphery of the latter, and a fillet of cast metal in said circular depression and engaging the exterior periphery of said disk to keep the latter permanently seated in said carrier.

2. A grinding disk of annular conformation, the interior periphery of said disk being adapted to act as a grinding surface, said disk being seated under pressure alongits exterior periphery within a carrier in a circular depression provided along the interior periphery of the-latter, and a fillet of cast metal in said circular depression and engaging the exterior periphery of said disk to keep the latter permanently seated in said carrier, a ring of yielding material interposed between said disk and an annular projection forming the bottom of said depression.

3. A grinding disk of annular conformation, the interior periphery of said disk being adapted to act as a grinding surface, said disk being seated under pressure along its exterior periphery within a carrier in a circular depression provided along the interior periphery of the latter, a circular groove within said depression, and a fillet of cast metal in said groove and engaging said disk near the exterior periphery of the latter.

4. A grinding disk of annular conformation, the interior periphery of said disk being adapted to act as a grinding surface, said disk being seated under pressure along its exterior periphery within a carrier in a circular depression provided along the interior periphery of the latter, and a fillet of cast metal in said circular depression and engaging a tapered surface provided on said disk near its exterior periphery.

5. In a device for producing threads by grinding, a rotatable annular grinding disk, the inner circumference of which is formed of two angularly disposed annular surfaces forming together a pointed annular grinding edge arranged in a carrier, including the steps of fitting said grind- A ing disk accurately in said annular groove and inserting a yieldable packing between'one wall of 'said groove and the adjacent inner face portion of said annular disk, applying a pressure upon the outer face of said grinding disk so as to com carrier to expand the same and thereby produce an annular clearance between the bottom of said annular groove and the outer circumference of said grinding disk, and then pouring molten metal into said annular clearance.

7. A method of securing an annular grinding disk with its outer circumference in an annular groove provided in the inner wall of a hollow carrier, including the steps of fitting said grinding disk accurately in said annular groove and inserting a yieldable packing between one wall of said groove and the adjacent inner face portion of said annular disk, applying a pressure upon the outer face of said grinding disk so as to compress said yieldable packing, heating said hollow carrier to expand the same and thereby produce an annular clearance between the bottom of said annular groove and the outer circumference of said grinding disk, and then pouring molten metal into said annular clearance and also into the corner formed between the outer face of said grinding disk and the inner wall of said hollow carrier to form a cast annular fillet which permanently holds the grinding disk in place in said holder.

8. In a device for producing threads by grinding, a rotatable annular grinding disk, the inner circumference of which being employed for producing the thread and being formed by two conical surfaces intersecting each other in a plane between the two end faces if said grinding disk, said conical surfaces forming an angle between eachother which is equal to the angle between two adjacent flanks of the thread to be produced.

9. In adevice for producing a thread by grinding, a rotatable annular grinding disk, the inner circumference of which being employed for grinding a thread into the circumference of a work piece having a circular cross section, the work engaging portion at the inner circumference of said annular grinding disk having a profile corresponding to the profile of the thread to be'produced.

.HERMANN HIPPLE.

press said yieldable packing, heating said hollow 

